We are now accepting submissions for session topics in two categories: sessions to be led by our Research In Motion® (RIM®) experts, and sessions to be led by you, members of the BlackBerry developer community. We have room on the schedule for eight sessions, of which four will be led by RIM experts, and four will be led by BlackBerry developers.

How do you participate? It’s simple. From now through Friday September 14th, you can propose a session topic via Twitter®, Facebook®, or in the comments below. If you want to send us a tweet, be sure to mention @BlackBerryDev, and remember to include the #BBUnconference hashtag.

Once we collect your suggestions, we’ll put it to a vote. The winning entries will become part of Unconference Day at BlackBerry Jam Americas – and four lucky community members will be invited to host their own sessions!

(If you miss the online voting, don’t worry. You can still propose sessions on-site in San Jose using the Unconference Schedule whiteboard.)

We’re committed to you, the BlackBerry developer community. Let’s work together to build an unforgettable Unconference Day that covers the topics you want to hear about the most.

So, what do you think? What sessions do you want to see on September 27th? Let us know on Twitter, on Facebook or in the comments. We’ll be listening.

BlackBerry Jam Americas – Sept 25-27, San Jose CA

BlackBerry® Jam Americas 2012 is a showcase for the bold, new direction BlackBerry is heading with the upcoming BlackBerry® 10 platform. The event attracts developers and industry leaders who understand the power of BlackBerry and want to build their success with the platform. Whether you’re a Native, Web, or Android™ developer, don’t miss this opportunity to explore the powerful, game-changing BlackBerry 10 platform.

Join us, September 25-27 in San Jose, California. Register Now and use promo code DJAA45 to register for only $299.00

I recently had the pleasure of chatting with Derek Konigsberg, who some of you may know better as @dkonigs. For those of you who may not know Derek, he’s been developing apps for the BlackBerry® platform since 2006 (starting with BlackBerry handheld software version 4.1), so he’s seen quite the overhaul to the platform. Long story short, my conversation with Derek about his questions on BlackBerry® 10 development inspired a really neat idea: Stump the BlackBerry Devs.

How do I stump someone and who am I stumping? Provide us with a design or mock-up that you think would be difficult to be implemented using our Cascades™ UI framework. The Cascades tools development team will try to implement your submission in a flexible manner that involves no hardcoding of values and that is flexible enough to handle multiple screen resolutions and multiple form factors.

Here are the details:

Mock up a design for a screen, making it as beautiful or as ugly as you like.

It doesn’t matter how you create it – use a professional design tool or draw it on a napkin.

Don’t worry about a data source, we’ll be using dummy data anyway.

Throughout the month of August, submit an image of your mock-up to the @BlackBerryDev Twitter® account using the hashtag #StumpTheBlackBerryDevs.

Final day for submissions will be August 31, 2012.

If an image isn’t worth a thousand words and you feel the need to describe your design with more than the 140 characters of Twitter will allow, feel free to submit multiple tweets to explain your design.

We’ll choose three of the most difficult or creative submissions and throughout the month of September, and then we’ll get to work implementing them using the R8 SDK beta release that Tim Neil talked about here.

At BlackBerry Jam Americas, we’ll host a session during the Unconference Day where we’ll reveal the chosen designs, explain how we implemented them, and walk you through the reasoning behind the approach taken. For any features of the design which could not be elegantly implemented, we’ll do a few things:

Implement the solution per the design using hardcoded values.

Provide an alternative solution that is consistent with Cascades design principles.

Explain the design decisions behind Cascades for why the solution could not be delivered per what you’d submitted.

If applicable, add new features to the roadmap which would allow this design to be implemented in future and publicly share the tracking of those features via the BlackBerry Developer Issue Tracker.

In parallel to the activities at BlackBerry Jam Americas, we’ll also post the code for the solutions to our open source repo at blackberry.github.com and will share a detailed walkthrough of the solution to this blog.

Sound like a fun challenge? I hope so. Now let’s see what you’re made of…can you stump the Cascades R&D team?